Many touch detection systems use reference data to detect when a touch has occurred on a touch surface (e.g., on a tablet or smartphone) and/or an amount of force associated with the touch. Although techniques for updating such reference data exist, new update techniques (e.g., new update criteria for deciding when to update reference data, the manner in which the reference data is updated, the contents or composition of the reference data itself, etc.) would be desirable. Such new update techniques are desirable because they permit faster touch detection and/or a more accurate force estimation.